It is known from New Zealand patent specification 233,083 that synthetic combinations of endophyte/herbage cultivars can be made which are resistant to pests and can be less toxic to grazing animals than naturally occurring combinations. These selected properties may be achieved by selecting synthetic combinations which produce relatively high levels of peramine and relatively low levels of or no lolitrem B in ryegrass.
U.S. Pat. No. 6,111,170 (the '170 patent), describes findings that selected endophytes of the genus Neotyphodium form stable synthetic combinations with tall fescue hosts (Festuca arundinacea). The combinations described have improved resistance to invertebrate pests as compared to tall fescue cultivars that do not contain such endophytes. The particular strains of endophyte described in the '170 patent include AR501, AR502, AR510, AR542, AR572, AR577 and AR584. This patent does not however describe, nor suggest other attributes of these endophytes and their combinations beyond improved pest resistance and reduced toxicity.
Russian patent abstract, RU2201678C2 describes a biopreparation for protecting plants against fungus and bacterial diseases. The biopreparation is based upon live cells and spores of endophytic bacterium Bacillus subtilis. This bacterium has a high antagonistic activity to agents of fungus and bacterial diseases in vegetable, grain and fruit cultures. No description is made regarding use of the bacterium in grasses. It is also not obvious from this abstract that the bacterium described is resistant to fungicides. The description merely makes reference to the bacterium preventing fungal infection of the plant in effect acting as a fungicide itself.
Meriaux et al describes the viability of ryegrass (Lolium perenne) seed infected with Neotyphodium endophyte after treatment with fungicides. The fungicides used were prochloraze (prochloraz), triticonazole, bitertanol, and fluquinconazole administered at two doses or heat treated (oven treatment at 60 or 80° C.). Seed germination is described as being effected for treatment with prochloraze (1 g/kg), triticonazole (5 and 10 g/kg) and heat treatment at 80° C. No reference is made or suggested towards endophyte viability or viability (seed or endophyte) when combined with cultivated grasses. It is the inventor's experience that seed viability and endophyte viability are two very different issues with seeds often retaining viability for longer than endophytes.
Rolston et al describes fungicide treatment effects on AR1 endophyte and ryegrass combinations. AR1 is a Neotyphodium species endophyte that has a different alkaloid profile to AR584 in that AR1 does not produce loline alkaloids and may produce terpendoles differently to AR584. The publication notes that AR1 endophyte viability was not affected by the fungicide treatments including triazole and strobilurin fungicides. It is the inventor's experience that it is not obvious that a property noted for one endophyte in one type of plant would also exhibit the same properties with another endophyte or plant. Anecdotal evidence exists showing that endophyte strain and plant species may result in very different results. One reason for the variation is that different endophytes give different attributes to grass endophyte combinations. One reason for the variation is that different endophytes have different levels and types of alkaloid profile. As a result different endophytes in combination with different grasses have variable properties. In addition, different species of grass also influence properties of combinations with endophytes.
Saiga et al describes the effects of Neotyphodium endophytes on plant characteristics including fungicide soak treatments. The fungicide, benomyl (benzimidazole group) is described as being effective in killing endophyte in both perennial ryegrass and tall fescue. Triforine (amide group) fungicide was effective in tall fescue and effective in some perennial ryegrass plants. Thiophanate-methyl (benzimidazole precursor fungicide) had little effect on endophyte in perennial ryegrass and had no effect on endophyte in tall fescue. The aim of the publication method is to remove endophytes altogether from the grass. As a result, particularly strong doses of fungicides are used and the grass is soaked in fungicide. No disclosure is made towards identification of endophytes with higher resistance to fungicides, or disclosure regarding stability.
Hill et al describes tall fescue cultivars containing endophytes including Neotyphodium coenophialum. The abstract discusses how to maintain viable endophyte in seedling plants by applying chloroneb (aromatic fungicide) and terrazole (thiazole group) fungicides during the first 7 to 21 days post germination. Hill et al does not identify endophytes with resistance to fungicides or identify AR584 as exhibiting any particular resistance. Further, the time period of analysis described is only post germination and only in seedling plants.
Park et al describes development of a microbial fungicide that utilises endophytic bacteria for the control of cucumber and red pepper anthracnoses caused by Colletotrichum orbiculare and C. coccodes and C. acutatum. Among 18 strains isolated, a bacterial strain EB215 isolated from cucumber roots displayed the most potent antifungal activity against Colletotrichum species. No mention is made regarding improved fungicide resistance due to endophyte, nor is usage in terms of grasses such as tall fescue.
Bluett et al describes a trial comparing various properties between ryegrass (Lolium perenne) infected with wild type endophyte, AR1 endophyte or no endophyte. AR1-infected ryegrass was found to produce similar pasture yields as wild endophyte-infected ryegrass, while offering small improvements in milk yield with no incidence of ryegrass staggers noted in grazing animals. No discussion is made on the endophyte effect with regard to fungicide treatment, endophyte stability or to the endophyte AR584 or tall fescue grass cultivars.
It should be appreciated by a person skilled in the art that an endophyte plant combination that has increased fungicide resistance would be of benefit to enhance existing turf and forage seed crop management practices. In addition, increased stability during transport would also be an advantage.
It is an object of the present invention to address the foregoing problems or at least to provide the public with a useful choice.
All references, including any patents or patent applications cited in this specification are hereby incorporated by reference. No admission is made that any reference constitutes prior art. The discussion of the references states what their authors assert, and the applicants reserve the right to challenge the accuracy and pertinency of the cited documents. It will be clearly understood that, although a number of prior art publications are referred to herein, this reference does not constitute an admission that any of these documents form part of the common general knowledge in the art, in New Zealand or in any other country.
It is acknowledged that the term ‘comprise’ may, under varying jurisdictions, be attributed with either an exclusive or an inclusive meaning. For the purpose of this specification, and unless otherwise noted, the term ‘comprise’ shall have an inclusive meaning—i.e. that it will be taken to mean an inclusion of not only the listed components it directly references, but also other non-specified components or elements. This rationale will also be used when the term ‘comprised’ or ‘comprising’ is used in relation to one or more steps in a method or process.
Further aspects and advantages of the present invention will become apparent from the ensuing description which is given by way of example only.